diff options
Diffstat (limited to 'src/passes/OptimizeInstructions.cpp')
| -rw-r--r-- | src/passes/OptimizeInstructions.cpp | 26 |
1 files changed, 10 insertions, 16 deletions
diff --git a/src/passes/OptimizeInstructions.cpp b/src/passes/OptimizeInstructions.cpp index 83bee9a0f..019d6bda1 100644 --- a/src/passes/OptimizeInstructions.cpp +++ b/src/passes/OptimizeInstructions.cpp @@ -1936,31 +1936,27 @@ private: } } } - // signed(x - y) <=> 0 => x <=> y - // + // x - y == 0 => x == y + // x - y != 0 => x != y // unsigned(x - y) > 0 => x != y // unsigned(x - y) <= 0 => x == y { + using namespace Abstract; using namespace Match; - BinaryOp op; Binary* inner; // unsigned(x - y) > 0 => x != y if (matches(curr, - binary(Abstract::GtU, - binary(&inner, Abstract::Sub, any(), any()), - ival(0)))) { - curr->op = Abstract::getBinary(type, Abstract::Ne); + binary(GtU, binary(&inner, Sub, any(), any()), ival(0)))) { + curr->op = Abstract::getBinary(type, Ne); curr->right = inner->right; curr->left = inner->left; return curr; } // unsigned(x - y) <= 0 => x == y if (matches(curr, - binary(Abstract::LeU, - binary(&inner, Abstract::Sub, any(), any()), - ival(0)))) { - curr->op = Abstract::getBinary(type, Abstract::Eq); + binary(LeU, binary(&inner, Sub, any(), any()), ival(0)))) { + curr->op = Abstract::getBinary(type, Eq); curr->right = inner->right; curr->left = inner->left; return curr; @@ -1970,11 +1966,9 @@ private: // This is not true for signed comparisons like x -y < 0 due to overflow // effects (e.g. 8 - 0x80000000 < 0 is not the same as 8 < 0x80000000). if (matches(curr, - binary(&op, - binary(&inner, Abstract::Sub, any(), any()), - ival(0))) && - (op == Abstract::getBinary(type, Abstract::Eq) || - op == Abstract::getBinary(type, Abstract::Ne))) { + binary(Eq, binary(&inner, Sub, any(), any()), ival(0))) || + matches(curr, + binary(Ne, binary(&inner, Sub, any(), any()), ival(0)))) { curr->right = inner->right; curr->left = inner->left; return curr; |